Does my morse control have a warm up position?

For the sake of closure I shall post the results - after 3 weeks of penetrating oil the tab moves!

I now have a neutral position with which I can rev the engine.

Thanks for the assistance.
 
To warm up or not to warm up? As the majority favour no warm up but somehow I was brought up to warm up for five minutes before casting off, I went back to check a Yanmar manual for the GM series. It advises

  • Do not run at full power until after five minutes of warm up
  • It is ok to run at up to half power during the first five minutes
I will modify my behaviour accordingly. On a related note, I remember advice from Pat Manley in PBO to run slowly for five minutes at the end of a voyage to cool an engine that has been working hard before stopping it.
 
Early in my sailing career, with little experience of diesels, I hired a boat. We had overnighted on mooring buoy very close to both an adjacent boat and the rocky Scottish shore. Leaving early in the morning and not wanting to disturb the neighbours, I left starting the engine until immediately before we dropped the mooring. Having cast off, I engaged gear and the engine stopped, leaving us drifting towards the rocks. Fortunately, the engine restarted before we hit them. I've subsequently always run the engine for a minute or so before departure.
 
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